A Couple Little Things I'm Wondering About


Two quick questions for anyone with any experience with either topic.

1. Why do some folks with usually higher end systems use those cable lifters to keep the cable elevated? What are they intended to do? If you use them, what do they do for you please? And if you know do they make sense from a purely technical standpoint? 

2. I bought a bunch of those gold plated caps to cover all the unused RCA jacks on the back of my AVR. I believe they are intended to keep noise down. If you use these, please comment on them. Do you think they do what they're supposed to do, and/or do they make sense from a purely technical standpoint?

Thanks!
jcolespeedway
i will let the other keyboard hero jockeys unload first - just sit back strap in
It depends:

how capacitive is your floor ?

does your electronic short to ground inputs not selected ?
Anything on which your cables rest can add it’s constants to their dielectrics.    That changes the permittivity and permeability.      If you’ve spent money in an attempt at bettering your reproduction, on good cables; you’ve detuned them (ie: resting on wool, synthetic fibers, etc).       The Naysayer Doctrine preachers may scoff, because of their 1800’s belief system, but- 20th Century science says that the electromagnetic current/signal travels outside the conductor ("waveguide") and through the dielectric.     Even wiki-scientists are aware:        https://en.wikipedia.org/wiki/Speed_of_electricity#:~:text=Speed%20of%20electromagnetic%20waves%20in....                                                Just one possibility, regarding cable lifters.
Ok on the covers, they do help depending on the type you use. They are for point to point, crosstalk, and noise reduction. Not so much the newer stuff. The older tube preamps, they can get a lot of crosstalk between different, sources. They still work quite well, just one source at a time, is an option too. Otherwise, they do dress it up a bit in the back, and keep the dust and tarnish down, on the actual contact area, until they are used.

Regards
+1 rodman99999  Electric current is a motion of electric charge. The same amount of electric charge that leaves the source comes back to it.  Energy has to be delivered different way.  It is delivered on the outside of the cable (most of it between wires, but some outside) in form of electromagnetic wave.  Even when AC current changes direction electromagnetic wave doesn't - it is always from source to load.  Electromagnetic wave around the wires travels thru dielectric.  This dielectric affects speed of electricity, capacitance, dielectric absorption etc.  When you place cable on the floor some small fraction of electromagnetic wave travels thru floor impacting a little dielectric constant (wood has higher dielectric constant than air).  How audible it is I don't know.  In my system cables hang in the air between amp and speakers, but with other cables I don't remember hearing any difference.  It does not mean there is no difference.  Some people have better hearing and better systems than mine.
Post removed 
The current doesn't travel anywhere it isn't a thing but a concept. Electric current is the rate of flow of charge carriers in the conductor not in the dielectric. Electromagnetic energy flows outside the conductor,  most of it not all of it.  All the energy that flows in the conductor is used up as heat. The flow is close to the speed of light the miniscule amount of flow that is affected by a carpet or wood floor is barely measurable much less audible. The cable risers do nothing but calm the neurosis of the user.  If placing cables on risers affected the sound then your music would have a staccato effect as the flow passed over them. The whole notion of cable risers is ludicrous. 
jcole, I have what you would call a reasonably high end system. I do not waste my money on any of that garbage. Cable elevators are just a cosmetic thing to show off your stupidly expensive cables. Any sonic improvement they make is purely psychological. As for shorting caps, I tried them once and did not note any improvement in the system's signal to noise ratio. I have never used them again. Careful ground management and balanced cables where ever you can are the way to go. 

The audio industry discovered a long time ago that there is a visual aspect to people's buying habits. If it looks cool it must sound better and psychologically it does....for a little while anyway. Look what they have done to turntables. My own philosophy is that if it looks cool don't buy it.
I would prefer to spend my money on good engineering and parts selection than shiney chrome parts. Compare an SME turntable to a VPI turntable. The SME is far superior but is mundane looking in comparison.   
Sorry, but speed of electricity in the wire is dielectric dependent and is far from the speed of light (around 0.6 of it).  In practical terms it is approx. 5ns/m in typical insulated wire and 3.33ns/m in the vacuum.
Since dielectric affects the speed of electricity it also affects capacitance, dielectric absorption etc.   As for audibility - I don't know, but don't know enough to call it ludicrous.  
Really ? If it was audible then the only way you wouldn’t have a weird staccato effect in your music is if the wire floated. Either have the cable float or lay on something having little holders every so many feet or inches would really mess up the music, you know if insulation touching something was audible.
Gimme That Old Time Religion, Gimme That old Time Religion...... (ad nauseam)      They’re still trying to evangelically compel those electrons ("charge carriers"), through a conductor (HALLELUJAH!).        Anyone interested in today’s science, can read the, ’Electric Drift’ section, of the aforementioned wiki-science article.               Particularly, the last sentence (since we’re talking AC).        Note that these things are measurable, established and documented.        When one of these faith-in-outdated-science, religious fanatics can prove (via any 20th Century Science/Physics) that the above factors have no bearing on what we’re hearing, I’ll accept their version of salvation.      Is there a purgatory, for repentant doubters, in the Naysayer Doctrine?
The drift velocity of electrons in copper wire is around 1 inch per minute!
Current occurs immediately almost at the speed of light.  Kijank is right that the dielectric affects the speed and field strength. But also important is the presence and distance to the return. If close the fields cancel out.
Staccato effect?  Sure, for people who can hear tiny change in few nanoseconds between supports  (hundreds of MHz). 
Let's assume that somebody can hear the difference.  To me it doesn't matter if this difference is real or it is only a placebo effect.  Outcome is the same.
With AC; electrons don't drift at all.     They oscillate over a distance of a few micrometers (.0000001 Meter = micrometer), without movement along the conductor.        
Jcolespeedway, most cable vendors and certainly most in these forums and on this thread would have a hard time providing a valid and quantitative reason for the impact of dielectric value especially for the cable most likely to be elevated, i.e speaker cables. Now you expected them to provide technical explanations which would require quantitative analysis of not only the impact of flooring material on cable impedance, but what potential qualitative impact that would have on an audio signal. Keep in mind it would take literally minutes to measure real world impacts of carpet, wood, etc. on cable capacitance and impedance which already have questionable impact at all. if they can't provide measurements or have a qualitative discussion as opposed to hand waving you can pretty much assume they are guessing.


Similarly if someone cannot talk intelligently about RF attenuation versus frequency of a case opening then they again are guessing. Not to mention that the connected cables will absorb and communicate orders of magnitude more RF than a small opening.
1. Why do some folks with usually higher end systems use those cable lifters to keep the cable elevated?

No idea why some folks use them. I use them because they greatly improve sound quality.
What are they intended to do?

Greatly improve sound quality. I've done demo's. Its easy to hear.
If you use them what do they do for you please?

Improve clarity, detail, soundstage depth, and focus.

And if you know do they make sense from a purely technical standpoint?

Probably. But it took a while. They would seem to make sense from a dielectric point of view. Everyone knows the importance of quality insulators in cable design. Then you go and lay your cables on carpet, or wood, or whatever that is nowhere near as good as teflon or other quality dielectric. Cable Elevators are actually ceramic insulators, designed to insulate and prevent the propagation of electric charges. 

So for a long time this seemed the most likely technical explanation. Until I coated mine with TC, which is highly conductive, and they work even better. So it can't be that. 

Cables vibrate a great deal. Hold one some time while playing music, you will feel it. What if the real reason is they hold up off floor vibrations while allowing the cable to move freely? This I think is the correct answer. Because the effect is greatly improved by using rubber bands to suspend the cables above the cable elevators. https://systems.audiogon.com/systems/8367#&gid=1&pid=10
All my cables- power cords, interconnects- are suspended on cable elevators with rubber bands. I don't do these things for no reason. You never in your life heard a system this good. 


2. I bought a bunch of those gold plated caps to cover all the unused RCA jacks on the back of my AVR. I believe they are intended to keep noise down. If you use these, please comment on them. Do you think they do what they're supposed to do, and/or do they make sense from a purely technical standpoint?

What is this obsession with technical explanations? If you hear it, will you not use it unless you can explain it technically? What if there's a great technical explanation, but you can't hear it doing anything? Will you buy it anyway?

Let me save you a whole lot of time and trouble. The vast majority of technical explanations are either wrong when used, or will be shown years later to have been wrong. The very few really good technologies (Tekton, DBA, etc) hardly anyone understands anyway. They're good, but nobody gets it. Even though DBA has been around decades still hardly anyone gets it.

So enough with the technical obsession already. 

So technically don't be technical, and everything will work out actually.

:-)

I do understand, ya just got to try somethings. I've spent my life around folks telling me what's wrong, BUT I was the guy fixing want they broke...

A lifetime!! You have to love to tinker, and be happy with your own accomplishments. Who cares what others think, I or you still fixed it, not BROKE it...Big difference...
Some are made to fix things, some are made to break things...

Regards
The religiously obtuse can't differentiate; how DC and AC currents each affect electrons and Electrical Drift, in a conductor.      Apparently, repeating the same erroneous, classical doctrine, is somehow comforting.   "Trust me, brother, AMEN!"         No surprise!       
"What is this obsession with technical explanations?"       Perhaps: because the OP ASKED, "And if you know do they make sense from a PURELY TECHNICAL standpoint?"         The views, discoveries and measurement methods of modern (20th Century and on) Science/Physics, regarding electricity/electromagnetism, offer explanations for what our senses can perceive.       This thread’s OP expressed a desire for such.      
Post removed 
To each his own experience and YMMV.  I was skeptical about cable elevators but decided what the hell give them a try . I have found they make a difference whether the cables are on wood floors or carpet. The benefit in my 2 systems was apparent right away . I'll +1 millercarbon on these statements he made.

" Greatly improve sound quality. I've done demo's. Its easy to hear "
" Improve clarity, detail, soundstage depth, and focus "
Easy enough to try for yourself. An option for you -  MusicDirect sells a few different elevators, you can select a version you want to try and if you don't hear a benefit in your system/room return them for a refund within their return period (cost to ship back is on you) . Likewise, they sell the caps so you can try them as well.



Make your own elevators out of cardboard. Take a listen. Please post results. 
Experimentation is (and always has been) the basis of scientific discovery.      It works in your listening room, as well (whatever the topic).       KUDOS, to those so disposed!
Make your own elevators out of cardboard. Take a listen. Please post results
Used elevators, listened , no difference. 

Of course this gives no useful information unless it was done in a controlled listening test and the results were repeatable. 
See what I mean jcolespeedway, tons of hand waving but not a real technical discussion no matter the expanding number of posts.

One person likes to use the word science a lot but offers no confidence they have any significant background in the related science. One likes to talk about vibrating cables but likely has never done the very easy work of measuring the level of induced signal in a vibrating cable.


I do encourage you to try out cable elevators just get someone else to raise and lower your cables without telling you what they have done.



"1. Why do some folks with usually higher end systems use those cable lifters to keep the cable elevated?"

What else is left for them to do?

2. I bought a bunch of those gold plated caps to cover all the unused RCA jacks on the back of my AVR. I believe they are intended to keep noise down.

Your questions both touch similar benefit.

From what I have seen on pictures, most of the cable elevators are too low.

Cable elevators of proper height help with vacuuming the floor. They have to be high enough that the vacuum cleaner can slide under them.

Covering unused connectors prevents dust from settling there.

I have covers for all the unused connectors. RCA, XLR, USB, 6.3 mm headphones, other (bi-amp) connectors on speakers, unused headphone connectors on Walkmen, etc. Covering only RCAs would be a half-baked approach.

I use rubber/silicon covers which cost a few dollars per bag that will probably cover all the connections you have.
I think I read once that most cable lifters are carefully engineered to make the user feel special and the seller to become wealthier.... but I may not be remembering correctly. 
Post removed 
I tried the lifter and the grounding caps....neither worked for my system.  No difference at all
Millercarbon has a splendid imagination.

And the people who heard my system, they all imagine the same?
How do you explain Deborah hearing it even with her eyes closed? 
https://systems.audiogon.com/systems/8367#&gid=1&pid=10
Your blind MDS hatred is getting the better of you again, Mike. 

Tweaks are pornography for audiophiles 
Shouldn't have gone there. Cut you slack for so long now, but Oh well. You did. Too late now.

Sounds like something a measurebator would say.

https://www.kenrockwell.com/tech/7.htm

See Equipment Measurebator: Bottom Level 1 (Hell).

You ever want to try and claw your way up from the bottom let me know. But first you have to knock off the insults and apologize. Yeah. Congratulations. You made the list. Bye!

facten
To each his own experience and YMMV. I was skeptical about cable elevators but decided what the hell give them a try . I have found they make a difference whether the cables are on wood floors or carpet. The benefit in my 2 systems was apparent right away . I'll +1 millercarbon on these statements he made. 

" Greatly improve sound quality. I've done demo's. Its easy to hear "
" Improve clarity, detail, soundstage depth, and focus "


Thanks. Unfortunately as you can see those of us actually willing to try and listen are outnumbered and insulted for the crime of being audiophiles with the audacity to LISTEN and CARE what things sound like.

They have driven off a number of highly accomplished audiophiles. We got rid of one, and a big one, so that's a start. This site needs a total house cleaning. Appreciate any and all help. 
Let me get this right. So now we can’t hear any of the noise created by our gear, wires, home circuitry, carpets or jittery sources when we play music loudly? That’s when we hear it the most! If the S/N ratio is 60db (below normal conversation) you can’t hear it? Yeah, that’s about as sophisticated as we thought back in 1975 when an AR turntable seemed quiet.
Is this supposed to be a zero-sum game where you either hear it or you don’t?
Noise is not a separate track to be measured and heard at the same time as the desired signal. The noise is part of the signal riding in its entrails like the Coronavirus, infecting and inflaming and generally causing mayhem to our systems.

My doc says my sore shoulder should respond to anti-inflammatories, so I take one . . . and I massage the sucker . . . and I apply heat . . . and I exercise it . . . and I do anything I can to relieve the inflammation regardless of whether or not I can identify the aspirin, heat, or massage as affecting a particular muscle. It’s better!
Apply some anti-inflammatories to your system and then turn it up and enjoy what you have wrought.

Skepticism is the opiate of the closet misanthropist—who expresses his derision for others’ findings/opinions by claiming his own are based upon ‘science’ but then refusing to provide the numbers proving cable elevators to be snake oil.
If you think that constantly tweaking and using things like cable elevators makes you an artist and not a measurebator as per Ken, then I don't think you understand what he was trying to communicate. Of course, the fact he was talking about creation as opposed to recreation really makes your point rather moot. I will guarantee you that when he prints a photo, or uses a monitor for review, he expects dead accurate color reproduction and would not take to kindly to a print shop deciding his choice of color tone was wrong.


There are some honest audiophile, at least honest with themselves who admit they are not trying for reproduction accuracy, and hence most measurements really don't matter. 


When you get to elevators and RCA covers, we are no longer personal preference in sound not artistry, except as some have pointed out, the elevators can look nice.
You don’t need science to tell you that an insulated wire laying on carpet will change the sound coming out of your speakers degrading the clarity, detail, soundstage depth, and focus is so nonsensical it’s laughable. All it takes is a bit of common sense. Do you elevate your lamp wires so it shines brighter? 
Hi definition light bulbs. Now there’s an idea. I saw an LED bulb on Amazon that had a bluetooth speaker in it!  Go for it!
mapman neglects to mention he is #1 on the Hateful 18. In fact he is the one who when I considered his total lack of contribution, awful record in terms of false information, and relentlessly insulting innuendo first made me realize there are people there simply is no upside to engaging. He knows this, knows it very well. The fact he doesn’t mention it is another stain on his character. Its dishonest and deceitful to hide his ulterior motives in wanting me banned. It must gnaw at him daily knowing one of the greatest most helpful contributors on the site considers him literally beneath contempt.
  Science?     We don't need no stinking science!          Gimme That Old Time Religion, Gimme That Old Time Religion......(ad nauseam)             
MC is "one of the greatest most helpful contributors on the site" (his own words), in exactly the same way as DJT is "the best thing that ever happened to Puerto Rico" (also his own words). 
Hit a nerve, eh? Oh well. The censorship bias is yet another reason for the list- which you will never get off of. So live it up.